This invention relates to improvements in casings or enclosures for electric storage batteries, such as lead-acid batteries used in the operation of motor vehicles, marine vessels, and the like. More particularly this invention pertains to an enclosure assembly which will prevent, contain and safely direct the force of any storage battery explosion.
As is well known an explosive gas is generated during the charging cycles of storage batteries such as lead-acid batteries which are commonly used in motor vehicles. When a battery is charging hydrogen and oxygen gases are formed. Should that combination of gases accumulate and come in contact with a spark or flame an explosion could result causing destruction to the battery and adjacent property. Should a person be near the explosion he or she could be seriously injured. Thus, lead-acid batteries have an inherent safety hazard not commonly recognized by battery users. Even batteries which use plates formed of lead-calcium alloys which reduce the evolution of hydrogen and oxygen are not totally safe.
Although the explosion hazard exits, it is not fully appreciated by battery users probably because battery explosions, fortunately, do not occur too frequently and when they do very little publicity is given to them. But, it is a fact that battery explosions have and do occur and people have been injured as a result. Thus, batteries should be made safer than they are so as to avoid physicial injuries. Very little, if anything at all, has been done to prevent, contain, or direct the force of battery explosions. This invention provides a safe battery which prevents, contains, or directs the force of an explosion and thereby greatly reduces the chances or injury to people and damage to property.
I have found during the course of my analysis and examination of a storage battery after a hydrogen-oxygen gas explosion, that the cover is considerably weaker than the casing. In that case the force of the explosion caused the cover to shatter resulting, unfortunately, in eye and facial injuries to a person who was near the battery at the time of the explosion. My invention, in one of its forms, overcomes that cover weakness thereby resulting in a battery enclosure which will tend to contain all explosions. It is noted that internal explosions may result when accumulated hydrogen and oxygen is ignited from an internal spark caused by short circuits between the plates or broken post straps, for example. Also, an external flame entering the battery cells through the fill holes could ignite the gases.
Even with my improved cover for the battery enclosures, all internal explosions could not be safely contained. Thus, it becomes necessary to direct the force of intense explosions away from the area where people would generally be located. My invention, in another form, provides structure which results in the force of an explosion being diverted downwardly and thus away from any person.
My invention also provides structure which will prevent battery explosions caused by an external flame entering the battery cells through the fill holes. The same structure results in efficient venting of the potentially explosive gases from the battery thereby reducing the chances of internally ignited explosions.